Hi Bobbi,
Yes. Solve360 uses something called workgroups for sharing information. Consider them like secret rooms with keys. If you put something in the room, nobody can see/edit it except those with the right keys. Please see the following link for a full explanation.
http://www.norada.com/answers > Users and sharing information ... (page 3 - Sharing data between Users).
Next concerning subcontractors, you may not want to even give subcontractors permission to access the system. Maybe you only want them to see certain projects. This is possible too. You can simply publish a project to them so they can see or edit a project, but not need to access your system. Please see:
http://www.norada.com/answers > Let’s do it ... (page 9 - Sharing Project information with others).